Remove all the OS X 10.6 SDK forward declarations.

base/base.gyp

Index: base/base.gyp
diff --git a/base/base.gyp b/base/base.gyp
index 9767a5bd6ef041cd0705cd670199648c96ae852c..af6dad7005c96ee15c3ac228530f4b0afb94b59b 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -415,7 +415,6 @@
         'lazy_instance_unittest.cc',
         'linked_list_unittest.cc',
         'logging_unittest.cc',
-        'mac/closure_blocks_leopard_compat_unittest.cc',
         'mac/foundation_util_unittest.mm',
         'mac/mac_util_unittest.mm',
         'mac/objc_property_releaser_unittest.mm',
@@ -641,11 +640,6 @@
             'win/win_util_unittest.cc',
           ],
         }],
-        ['OS=="mac"', {
-          'dependencies': [
-            'closure_blocks_leopard_compat',
-          ],
-        }],
       ],  # conditions
       'target_conditions': [
         ['OS == "ios"', {
@@ -993,69 +987,6 @@
         },
       ],
     }],
-    ['OS=="mac"', {
-      'targets': [
-        {
-          'target_name': 'closure_blocks_leopard_compat',
-          'sources': [
-            'mac/closure_blocks_leopard_compat.h',
-          ],
-          'conditions': [
-            ['mac_sdk == "10.5"', {
-              'type': 'shared_library',
-              'product_name': 'closure_blocks_leopard_compat_stub',
-              'variables': {
-                # This target controls stripping directly. See below.
-                'mac_strip': 0,
-              },
-              'sources': [
-                'mac/closure_blocks_leopard_compat.S',
-              ],
-              'xcode_settings': {
-                # These values are taken from libSystem.dylib in the 10.5
-                # SDK. Setting LD_DYLIB_INSTALL_NAME causes anything linked
-                # against this stub library to look for the symbols it
-                # provides in the real libSystem at runtime. When using ld
-                # from Xcode 4 or later (ld64-123.2 and up), giving two
-                # libraries with the same "install name" to the linker will
-                # cause it to print "ld: warning: dylibs with same install
-                # name". This is harmless, and ld will behave as intended
-                # here.
-                #
-                # The real library's compatibility version is used, and the
-                # value of the current version from the SDK is used to make
-                # it appear as though anything linked against this stub was
-                # linked against the real thing.
-                'LD_DYLIB_INSTALL_NAME': '/usr/lib/libSystem.B.dylib',
-                'DYLIB_COMPATIBILITY_VERSION': '1.0.0',
-                'DYLIB_CURRENT_VERSION': '111.1.4',
-
-               # Turn on stripping (yes, even in debug mode), and add the -c
-               # flag. This is what produces a stub library (MH_DYLIB_STUB)
-               # as opposed to a dylib (MH_DYLIB). MH_DYLIB_STUB files
-               # contain symbol tables and everything else needed for
-               # linking, but are stripped of section contents. This is the
-               # same way that the stub libraries in Mac OS X SDKs are
-               # created. dyld will refuse to load a stub library, so this
-               # provides some insurance in case anyone tries to load the
-               # stub at runtime.
-               'DEPLOYMENT_POSTPROCESSING': 'YES',
-               'STRIP_STYLE': 'non-global',
-               'STRIPFLAGS': '-c',
-             },
-           }, {  # else: mac_sdk != "10.5"
-             # When using the 10.6 SDK or newer, the necessary definitions
-             # are already present in libSystem.dylib. There is no need to
-             # build a stub dylib to provide these symbols at link time.
-             # This target is still useful to cause those symbols to be
-             # treated as weak imports in dependents, who still must
-             # #include closure_blocks_leopard_compat.h to get weak imports.
-             'type': 'none',
-           }],
-         ],
-       },
-     ],
-   }],
     # Special target to wrap a gtest_target_type == shared_library
     # base_unittests into an android apk for execution.
     # TODO(jrg): lib.target comes from _InstallableTargetInstallPath()